PURPOSE: To provide complete coupling with a simple device by fitting a sealing member in a coupling member fixed to a retainer on the manipulator side, and operating a gripping mechanism through a bellows by action of an expansion/contraction drive mechanism provided in it so as to be capable of gripping an object to be retained.

CONSTITUTION: A base part meets a fitting part 12 formed at an object 11 to be retained such as an electronic apparatus to form a cylindrical coupling member 10 fixed on the retainer 13 of the arm of a manipulator, for example, in which a sealing part 14 is provided. The sealing part 14 is constituted so that a bellows may be expanded and contracted through a jointing rod 21 by action of an expansion/contraction drive mechanism 16 of ball screw construction with a motor 17 serving as a drive source. A gripping mechanism 22 consisting of a pair of finger members 23, 24 is jointed to a drive member 20 supported at the front end part of the bellows 15, so as to be capable of gripping a gripping part 12a formed at the fitting part 12 from both sides at the locking parts 23a, 24a provided at the front end of respective finger members 23, 24.